In Super Smash Bros. Brawl

Manaphy uses Heart Swap when coming out of a Poké Ball. This switches the controls of the players of the two characters closest to Manaphy when it launches the attack. Damage meters are also swapped, and if a character is knocked out, the player controlling the character at that time loses a stock (instead of the player who originally controlled that character). After approximately 15-30 seconds, the controls will be returned to normal.

Manaphy has a possibility of being able to swap four brawlers' hearts if all four are close enough to it.

In the anime

Manaphy

The user employs its psychic power to switch stat changes with the foe.

The ends of Manaphy's antennae glow pink and each produce a pink energy from them. The two energy balls find a Pokémon or human, and when both energies touch the opponent, their souls are switched. The switched bodies have their own voice, and their eye color changes to light blue. After a while, the effects fade.